The present invention is directed to coaxial cable connectors and, in particular, to coaxial cable connectors having a modular design whereby a two or three-piece connector can be implemented.
Coaxial cable is constructed with a center conductor surrounded by a dielectric material and air-housed in a metallic sheath. The relationship between the center conductor, dielectric, air and sheath determines the cable's characteristic impedance and its electromagnetic signal carrying performance.
In community antenna television (CATV), also known as cable television, coaxial cable is widely used and connected to various types of equipment using differently sized connectors, depending on the particular circumstances. For example, connectors are needed for trunk and distribution lines in a cable system. Typically, such cable lines have a characteristic impedance of 75 Ohms, and thus any connector used for terminating such trunk or distribution lines have a similar impedance value. Generally, a coaxial cable connector terminates both the center conductor and outer conductor (sheath) of the coaxial cable without damaging those components with the termination mechanism.
There are numerous known cable connectors. For example, Morris U.S. Pat. No. 4,854,893 discloses a coaxial cable connector having a ferrule 36 that "floats" within a housing 28 to permit the ferrule to accommodate receiving a seamed sheath of a cable, a somewhat distorted or deformed sheath of a cable or a noncircular sheath of a cable. However, even with such a "floating" ferrule arrangement, the sheath of a coaxial cable will contact the ferrule upon cable insertion into and cable removal from the connector. That is, ferrule 36 will almost always make contact with sheath of a cable during insertion and removal. Accordingly, unfettered insertion and removal of a cable is not possible with a structure like that disclosed by Morris.
Other cable connectors include sheath gripping mechanisms that include a gripping ferrule having a ramped surface at one end only thereof, whereby unbalanced gripping occurs. Blanchenot U.S. Pat. No. 3,706,958 and Nepovim U.S. Pat. No. 3,846,738 are examples of such mechanisms.
Since connectors are often attached to and removed from ends of coaxial cables in the field, a connector that provides simple and consistent connection is desirable. Furthermore, some field workers are familiar with connectors having a two-piece design while others are more comfortable using a three-piece design. Accordingly, it would be advantageous to have a coaxial cable connector that provides a superior gripping mechanism that can be implemented in either a two or three-piece connector structure.